Good-bye DRAM, hello flash?

EcoRAM comes from Spansion (previously a joint venture of AMD and Fujitsu), while Virident brings to the table a silicon, software, and hardware platform called GreenGateway, designed to effectively transform flash RAM into DRAM-class memory. Combining the technologies opens up the opportunity for organizations running data-centric Web apps — ones that perform frequent reads and infrequent writes — to do with one server what they previously could do with four, the companies say. Given the struggles organizations are facing with high energy costs, limited power budgets, and finite datacenter space, that’s significant.

[ Other vendors are touting memory as a means of boosting server efficiency. For more, please read “Memories of green.” ]

“There is a class of applications in datacenters that are constrained by the addressable main memory a server can handle,” says Rufus Connell, vice president, North American ICT (Information and Communication Technology) Research Practice for consulting company Frost & Sullivan. “As memory-bounded apps such as search use grow, conventional server architectures are failing to keep up with the increasing number of queries per second from consumers, which means more servers are needed and more power is needed to run and cool them. It is a real problem for datacenter operators globally, and a solution to help save energy and reduce total cost of ownership is needed sooner rather than later.”

The kind of applications Connell is alluding to require a high level of memory sitting on the motherboard, close to the CPU, such that it can access and deliver data quickly. “Today’s servers were not built with the data-centric needs of the Internet in mind. As a result, compute-centric servers in Internet datacenters can be made far more efficient with faster access to larger main memories,” says Raj Parekh, co-founder and CEO of Virident (and former CTO at Sun). “We created GreenGateway to enable flash memory to replace DRAM and deliver performance and energy efficiency. … The platform will enable Internet companies to access far larger main memories, achieving growth while living within the pressing power, space, and cost constraints of the datacenter.”

The companies are currently targeting search as the application for their technologies, but they expect EcoRAM and GreenGateway can be effectively applied to applications such as data mining, databases, and biometrics. “I wouldn’t call it a niche technology. We’re probably talking about 40 to 50 percent of servers out there,” says Hans Wildenberg, executive president of Spansion’s media storage division.

The companies argue that their flash memory trumps DRAM in a number of ways. For example, DRAM is limited by energy constraints at the DIMM level and a limited number of DIMM sockets. “The typical DIMM is 2GB to 4GB. We can build up to 32[GB],” says Wildenberg, and that’s in part thanks to the fact that EcoRAM consumes one-eighth the power of DRAM.

Notably, the companies say they’ve devised a way to rearchitect the memory subsystem so that it is still compatible with existing server designs. This is accomplished by leveraging the standard memory DIMM form factor while requiring little platform modification.

The result is higher density: “If you have a 32GB server today [from DRAM] … we can move that server straight to 128[GB] or 256[GB] or 512GB,” he says.

A year from now, in fact, he expects to see servers with a full terabyte of flash memory.

Moreover, they say that EcoRAM is superior to NOR flash, which has slower write performance and lower density than required by the data-centric applications they’re targeting.

Performance is a critical component in all this, of course, given that the companies are targeting applications that require extremely fast reads. The company says, for example, that its EcoRAM is around 800 times faster at reads than NAND flash. At the moment, however, it performs at 80 percent of the speed of DRAM-only, according to John Nation, director of corporate marketing at Spansion. “[We] expect to be at virtually the same level with final silicon and software from the two companies,” he adds.

Now rather than messing with new flavors of in-server memory to boost performance, what about using attached storage such as SSDs (solid-state drives) as a supplement, you might wonder. Wildenberg says they can’t deliver the performance users need from these types of applications. “Solid state is not able to handle these types of applications. Users would not be able to have the experience of instance access,” he says.

I decided to run this technology past InfoWorld senior analyst Mario Apicella for his perspective, as he lives and breathes storage. His take: “Storage vendors like EMC, who don’t have control over servers, will swear on deployment within the storage domain and will ridicule others such as Sun, HP, and IBM, who are considering instead deployment inside the server.”

He continues: “I am convinced that these two different approaches serve different requirements and that there is room for both in a datacenter. However, the server I/O bottlenecks we bumped into while doing the SATA drives review are real, and deploying flash as an extension of DRAM will bypass that narrow I/O path.”

As always, the proof will be in the pudding. For the time being, the companies have had undisclosed companies testing prototypes of the memory technology. They’re also currently in talks with server vendors and OEMs. Expect to see EcoRAM products shipping once summer ends.